An electricity storage device, as a power source, is mounted on electric vehicles, hybrid vehicles, and the like. In a case of the electricity storage device, a plurality of electricity storage modules, each including a plurality of secondary battery cells, such as lithium-ion secondary battery cells, are arranged and housed.
The electricity storage modules are electrically connected via wire harnesses connected to external terminals. A large current flows in the wire harnesses when charging/discharging the electricity storage device, and thus, the wire harnesses are members having large thicknesses and small resistances.
Conventionally, a power-supply device in which a plurality of holder cases, each housing a predetermined plurality number of electricity storage modules, are housed in an outer case is known. The power-supply device has a structure in which concave parts are provided on the respective holder cases and a power-supply line formed of a metal plate is fit into the concave parts. By the structure, even when the power-supply device is shaken by vibration or the like during running of a vehicle, breakage of connecting terminals due to vibration of the power-supply line is prevented (for example, refer to JP 2001-6643 A).